How to use the TOS WHN 13 CNC

Safety first. Always follow the manufacturer’s manual and safety instructions for your machine before anything here. This page is general information only, not a substitute for the manual or for proper training. Read the disclaimer.

General operating notes for the TOS WHN 13 CNC horizontal borer. Control layouts and procedures vary between versions; check your manual for anything specific to your machine.

For the manual, spares and support, go to the maker’s official site: tosvarnsdorf.cz/en.

This machine at a glance

Speed: 10–3000 rev/min (variable)
Motor: 37 kW
Spindle: 130 mm, ISO 50 taper
Travels: spindle 800 mm

Use the horizontal borer operating guide for setting up, line boring, the facing head and spindle extension.

TOS Varnsdorf CNC table-type horizontal borer, 130 mm spindle; main motor 37 kW S1 (46 kW S6). Travels depend on the build, so they are not listed here. Older manual WH 13 / WHN 13 machines have different speeds and motors.

Work out speeds for this machine →

Setting up

Check the machine is level and the table, column and headstock ways are clean and oiled. Clear swarf from the table T-slots before you clamp anything.
Check the spindle taper and the tool shank are clean and undamaged. Seat the tool fully and tighten the drawbar or drift-key retention as your manual describes.
Know where the axis locks are. Lock every axis you are not feeding: the headstock on the column, the table slides and, where fitted, the spindle sleeve. Unlocked axes are the most common cause of chatter on a borer.
Plan the job so that the spindle stays as short as possible. Every extra length of spindle or bar sticking out reduces stiffness.

Tramming and indicating the work

Clamp the work lightly first. Mount a dial indicator in the spindle and sweep a datum face or edge while you move the table, then tap the work square before tightening the clamps fully.
To pick up an existing bore, sweep it with the indicator by turning the spindle by hand, and move the headstock and table until the reading is even all round.
For a rotary table, indicate the table centre and its zero position before you set the work on it.
Re-check the indicator after the final clamping: heavy work can move as it is clamped.

Line boring with an outboard support

For long or in-line bores, use a line bar carried in the spindle and supported at the far end in the outboard (end) support bearing.
Align the end support to the spindle with an indicator before you pass the bar through. The bar should turn freely by hand with no tight spots.
Set each cutter on the bar to size with a setting gauge or micrometer and lock it. Take a test cut and measure before you commit to the full length.
With the bar supported at both ends you can usually run nearer the normal speed. Without support, a long bar needs the slower speeds shown by the calculators.

Using the facing head

The facing head is used to face large surfaces and to bore or recess large diameters. Its radial slide carries the tool out from the centre as the head turns.
Engage and disengage the facing head drive only as your manual describes, normally with the spindle stopped.
Set the slide stops and check the tool clears the work and the clamps through a full turn by hand before you start the motor.
An offset slide and tool are out of balance. Use the head’s own, slower speed range, keep the slide no further out than needed, and use any balance weights provided.
Work out the speed from the diameter the tool is actually cutting at, not the size of the head.

Spindle extension

Feed the spindle out only as far as the cut needs. Stiffness falls off quickly as the spindle extends.
Where the job allows, move the table or column instead of extending the spindle, and lock the spindle sleeve once it is in position.
If the cut starts to chatter as the spindle extends, slow the spindle, reduce the depth of cut, or move the work closer.

Speeds and feeds

Use the RPM calculator or speeds & feeds with a horizontal borer chosen in the machine picker. Enter the bar overhang and bar diameter, and tick the facing head box if you are using it.
Our speed reductions for long bars (by overhang ÷ diameter, L/D) and for the facing head are rules of thumb est., not published data. Start lower and work up while listening to the cut.
Geared machines have fixed steps. Pick the nearest step at or below the suggested speed, and change gear only as your manual describes.

Safety

Keep clear of the rotating spindle, the facing head and any bar sticking out. A turning facing head can catch clothing well away from the cutter.
No gloves, loose sleeves, ties or jewellery near the spindle. Wear eye protection, and safety boots when handling heavy work.
Use proper lifting gear and rated slings for heavy work and fixtures. Never stand under a suspended load.
Stop the spindle before measuring, clearing swarf or adjusting the tool. Use a brush or hook for swarf, never your hands.
Know where the emergency stop is, and keep the area round the table travel clear.

Shutting down

Stop the spindle, withdraw the spindle and return the axes to a safe position. Isolate the machine.
Clean the table and ways, then oil them as your manual lists.

Not affiliated with or endorsed by TOS Varnsdorf. TOS is a trademark of its owner. See trademarks.